("electron in a finite square potential well") electron can travel within a thin conducting tube, consisting of three electrically disconnected segments. the first and the third segment are at the potential и--9 v, whereas the second one is at ½ 0 v, both measured with respect to the ground. the electron has kinetic energy ke-2 ev in the region with potential v. (a) what is the kinetic energy of the electron in the middle region? (b) sketch a graph of the potential energy of the electron as a function of the distance from the center of the tube. assume each piece has a length l (c) usually, the electron will simply pass through. however, while in the central region, if the electron emits a photon, it can lose enough kinetic energy to become trapped between -l/2 and +l/2. the energy levels of the electron within the trap are: e ev, e2-2 ev, and es-4 ev, and the non-quantized region begins at e4-9 ev. what is the smallest energy the emitted photon can have?